rossnixon,
Typically a fat32 drive will work fine to resolve this issue. Make sure that the partition is not only created but also formatted and healthy. What knoppix wants to do is create a file on this fat32 partition to use as a swap file. I haven't ever used BootitNG but you can use the utilities "fdisk" and "format" off of any windows boot disk to create this. One note though...running knoppix this way (without adequate memory) does not work very well. In my experience it is very slow, almost to the point of not being usable. Best of luck

fsl